FILE – In this Friday, Jan. 12, 2018 file photo, President Donald Trump shakes hands with White House physician Dr. Ronny Jackson as he boards Marine One to leave Walter Reed National Military Medical Center in Bethesda, Md., after his first medical check-up as president. On Wednesday, March 28, 2018, President Donald Trump fired Veterans Affairs Secretary David Shulkin, and tweeted that Jackson is his nominee to replace Shulkin. (AP Photo/Carolyn Kaster)